The SelectionDAGBuilder's handling of debug info, on rare

occasions, caused code to be generated in a different order.
All cases I've seen involved float softening in the type
legalizer, and this could be perhaps be fixed there, but
it's better not to generate things differently in the first
place.  7797940 (6/29/2010..7/15/2010).



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@108484 91177308-0d34-0410-b5e6-96231b3b80d8

1 files changed, 22 insertions, 0 deletions

diff --git a/lib/CodeGen/SelectionDAG/SelectionDAGBuilder.h b/lib/CodeGen/SelectionDAG/SelectionDAGBuilder.h
index 46733d6db1..bc3fd62c3f 100644
--- a/lib/CodeGen/SelectionDAG/SelectionDAGBuilder.h
+++ b/lib/CodeGen/SelectionDAG/SelectionDAGBuilder.h
@@ -64,6 +64,7 @@ class PHINode;
 class PtrToIntInst;
 class ReturnInst;
 class SDISelAsmOperandInfo;
+class SDDbgValue;
 class SExtInst;
 class SelectInst;
 class ShuffleVectorInst;
@@ -93,6 +94,24 @@ class SelectionDAGBuilder {
   /// to preserve debug information for incoming arguments.
   DenseMap<const Value*, SDValue> UnusedArgNodeMap;
 
+  /// DanglingDebugInfo - Helper type for DanglingDebugInfoMap.
+  class DanglingDebugInfo {
+    const DbgValueInst* DI;
+    DebugLoc dl;
+    unsigned SDNodeOrder;
+  public:
+    DanglingDebugInfo() : DI(0), dl(DebugLoc()), SDNodeOrder(0) { }
+    DanglingDebugInfo(const DbgValueInst *di, DebugLoc DL, unsigned SDNO) :
+      DI(di), dl(DL), SDNodeOrder(SDNO) { }
+    const DbgValueInst* getDI() { return DI; }
+    DebugLoc getdl() { return dl; }
+    unsigned getSDNodeOrder() { return SDNodeOrder; }
+  };
+
+  /// DanglingDebugInfoMap - Keeps track of dbg_values for which we have not
+  /// yet seen the referent.  We defer handling these until we do see it.
+  DenseMap<const Value*, DanglingDebugInfo> DanglingDebugInfoMap;
+
 public:
   /// PendingLoads - Loads are not emitted to the program immediately.  We bunch
   /// them up and then emit token factor nodes when possible.  This allows us to
@@ -345,6 +364,9 @@ public:
 
   void visit(unsigned Opcode, const User &I);
 
+  // resolveDanglingDebugInfo - if we saw an earlier dbg_value referring to V,
+  // generate the debug data structures now that we've seen its definition.
+  void resolveDanglingDebugInfo(const Value *V, SDValue Val);
   SDValue getValue(const Value *V);
   SDValue getNonRegisterValue(const Value *V);
   SDValue getValueImpl(const Value *V);